Form work for concrete construction

ABSTRACT

Arched form panels for use in concrete construction are provided. The panels are constructed to deform under load towards support beams. They can be held in place by clips which are removable when the concrete has set.

ilnited States Patent [1 1 Fox [451 Nov. 4, 1975 FORM WORK FOR CONCRETE CONSTRUCTION [76] Inventor: Ronald Fox, c/o Mrs. M. Smith, 25

Snydale Road, Normanton, Yorkshire WF61NT, England [22] Filed: Sept. 6, 1973 [21] Appl. No.: 394,617

[30] Foreign Application Priority Data Sept. 7, 1972 Australia 356/72 Dec 12, 1972 Australia 1590/72 [52] US. Cl. 249/23; 52/329; 52/499; 248/228; 249/211 [51] Int. Cl. E04G 11/04; E04B 5/54 [58] Field of Search 249/19-26, 249/210-212, 209, 28, 29, 30; 52/85;

[56] References Cited UNITED STATES PATENTS Spaulding 52/87 Schuller 249/23 881,299 3/1908 Chezem 249/209 938,718 11/1909 Smith 249/211 1,375,288 4/1921 Goldie 52/330 X 1,652,056 12/1927 Selway 249/24 1,914,033 6/1933 Miller 249/24 2,480,642 8/1949 Galloway 4 t 1 52/86 3,195,209 7/1965 Klausner 52/326 X 3,294,357 12/1966 Tooley 249/28 Primary ExaminerFrancis S. Husar Assistant ExaminerJohn S. Brown Attorney, Agent, or FirmWaters, Schwartz & Nissen ABSTRACT Arched form panels for use in concrete construction are provided. The panels are constructed to deform under load towards support beams. They can be held in place by clips which are removable when the concrete has set.

6 Claims, 8 Drawing Figures US. Patent Nov. 4, 1975 Sheet 1 of 4 US. Patent Nov. 4, 1975 Sheet 2 of4 3,917,215

US. Patent NOV.4, 1975 Sheet3 014 3,917,215 I 291 121 291 201 j 301 H x g i 301 U.S. Patent Nov. 4, 1975 Sheet 4 of 4 Fig.8.

FORM WORK FOR CONCRETE CONSTRUCTION This invention relates to improvements in and relating to form-work for concrete construction.

Elevated floors are normally constructed by erecting a false floor of form-work supported by a plurality of adjustable props and then pouring the concrete onto the false floor, laying at the same time the necessary reinforcing material. The setting up of the false floor on the props takes considerable time and after the concrete floor has cured sufficiently, the false form-work floor is removed by slackening off the adjustable props to enable the concrete supporting form-work to be taken down. This operation adds considerable time to the overall time of erection of the floor.

It is an object of this invention to provide a simplified means for erecting form-work for pouring elevated concrete floor slabs. Other objects and advantages of the invention will become apparent from the following description.

With the foregoing and other objects in view a method is provided of forming between a pair of parallel horizontally extending elevated support beams, a removable false floor upon which wet concrete may be placed to form a slab, comprising the steps of:

a. placing and arranging a plurality of complementary form panels between said beams in operative concrete supporting attitudes, each panel being adapted to extend between said beams and to fit neatly together in side by side abutting relationship along said beams; and

b. affixing removable panel support means to said beams to support said panels therebetween in their said operative attitudes to enable wet concrete to be supported thereon; whereinsaid panels may be removed from said operative attitude between said beams'by extracting said panel support means after a concrete slab formed thereon has set.

Preferably, in the method, said panels are supported adjacent the lower edges of said beams so that said beams may be enveloped by concrete poured on said removable false floor thereby becoming an integral part of a slab formed thereabove.

In another aspect, a form panel is provided for use in carrying out the method, wherein said panel is of substantially rectangular form and is arched upwardly from the two parallel edges of said panel which engage with said beams and is made of resiliently deformable material, whereby when said panel is loaded with wet concrete the vertical load of the concrete tends to deflect the form panel downwardly thus urging said engaging edges firmly against said beams providing an effective seal between said form panel and said beams and an effective load transfer means from said panel to said beam.

Preferably, in the form panel, the edges of said panel are stiffened by means of a downwardly extending peripheral web arranged to prevent non-uniform deflection of said edges.

More preferably, the form panel is apertured at or adjacent said engaging edges to enable one or more removable clips to be inserted therethrough and into engagement with said beam to affix said form panel to said beam, said clips constituting said panel support means.

In yet another aspect, this invention contemplates an apparatus for forming a removable false floor upon 2 which wet concrete may be placed to form a slab, said apparatus including at least" a. a pairof support beams which are adapted to be erected at an elevated position, at which they extend horizontally and parallel to one another, and to cooperate with removable panel support means; and,

b. a plurality of arched form panels arranged to fit neatly between said beams and to be affixed thereto by means of said support means; said panels being removable from their operative attitude between said beams by extracting said panel support means after a concrete slab formed thereon has set.

Preferably, in the apparatus according to the invention, each of said support beams comprises a vertically disposed bearing surface adaptedto co-operate with said panels by bearing against their edges when they are loaded and at least one horizontally disposed loadbearing member adapted to co-operate with said support means by preventing downward movement of said support means when said panels are loaded.

More preferably, said beam comprises at least one vertically disposed web and at least one horizontally disposed web.

Yet more preferably, said beam comprises a horizontally disposed flange at the lower end of a vertically disposed web, said horizontally disposed flange having a vertically disposed flange at its edge remote from the vertically disposed web.

Preferably, said horizontally disposed flange is adapted to be connected to a plate comprising said support means.

Alternatively, said beam comprises in addition a horizontally disposed internal web adapted to bear downwardly against the upper leg of a U-shaped clip, and wherein said horizontally disposed flange is adapted to bear downwardly against the lower leg of said U-shaped clip, said clip constituting said panel support means.

Again, preferably each of said form panels is of substantially rectangular form and is arched upwardly from the two parallel edges of said panel which engage with said beams and is made of resiliently deformable material, whereby when said panel is loaded with wet concrete the vertical load of the concrete tends to deflect the form panel downardly thus urging said engaging edges firmly against said beams providing an effective seal between said form panel and said beams and an effective load transfer means from said panel to said beam.

More preferably, the edges of said panel are stiffened by means of a downwardly extending peripheral web arranged to prevent non-uniform deflection of said edges.

Furthermore, the form panel may be apertured at or adjacent said engaging edges to enable one or more removable clips to be inserted therethrough and into engagement with said beam to affix said form panel to said beam, said clips constituting said panel support means.

In order that the invention may be more readily understood and put into practical effect, reference will now be made to the accompanying drawings which illustrate preferred forms of the invention, and wherein:

FIG. 1 is a perspective view of a form panel according to the invention;

FIG. 2 is a partially cut-away perspective view of a false floor assembly;

FIG. 3 is a side elevational view of a false floor assembly under load, for example, by a slab of wet concrete;

FIG. 4 is an enlarged detail of the left hand portion of the false floor assembly shown in FIG. 3 indicating the forces involved;

FIG. 5 is a side elevational view of an end portion of a false floor assembly, showing an alternative embodiment of a form panel according to the invention in cross-section;

FIG. 6 is a side elevational view of an end portion of a false floor assembly showing yet another embodiment of a form panel according to the invention and another embodiment of a beam;

FIG. 7 is a side elevational view of another embodiment of a beam, form panel and support means showing one prop and a concrete slab and floor slab in crosssection; and

FIG. 8 isa variation of the enlarged detail shown in FIG. 4 illustrating the advantages of the invention.

Referring now to FIGS. 1 to 4 and 8, there is shown an arched form panel 10 supported between a pair of side support beams 11. The side support beams 11 are preferably roll formed from thin gauge steel plate and are formed into an I-beam shape by connecting together two beams in back-to-back relationship. The beams 11 are adapted to extend at, for example, four foot spacings, across a building area between side support walls. If necessary support posts can be provided intermediate their ends. Each arched form panel 10 is suitably about four feet wide by three feet long. The arched form panel has an upper main body portion 14 and is provided with a surrounding peripheral web or side walls 15. These side walls extend downwardly and are located in a vertical plane when the form is supported between the beams 11. The end walls 16 are each provided with a pair of apertures or slots 17 through which U-shaped support or clip members 18 are inserted from the inside to engage the respective beam 11 to connect the arched form thereto.

The clip members 18 pass through the slots 17, across the upperedge 19 of the upturned portion 20 of flange 12 of the beam 11 and the outermost end 21 of the clip member 18 engages beneaththe internal web or stop member 22 fixed to the inner web 23 of the beam 11. The lower portion 24 of the clip engages the underside of the beam 11 and terminates in a downwardly extending tag 25.

When the form panel 10 is supported in the above manner, concrete supported thereby will tend to flatten the arched form panel 10, accompanied by spreading of the end walls 16. This spreading is resisted by the beams 11 so that the vertical load supported by the central portion of the arched form is transformed into side thrust against the beams 11 and shear between the form 10 and the upturned flange 20. This shear is taken by the upper plate 26 of the clip members 18. Thus the arched form panel 10 is load supporting without the necessity for providing intermediate supports between the beams 11.

Considering FIGS. 4 and 8 in more detail, an arched form panel 10 is made of resiliently formable material. If the panel is loaded as shown in FIG. 3 with an evenly distributed load Llbf. per foot then the centre unsupported portion of the arched panel will deflect downwards resulting in spreading of the panel causing the vertical end bearing portions to jam between the complementary vertical engaging portions of the restraining beams.

As shown in FIG. 4 this evenly distributed load will cause a load at the supported end of P the vertical ment of form panel 102 is restrained. However, this 4 shear load, and P the substantially horizontal force caused by the deflection of the arch. The greater the deflection, the greater the force P The horizontal component R of the force P will result in a friction force F; due to the contact between the complementary bearing surfaces of the panel in the support beam. The friction force F is not sufficient to equate to the total vertical load W and the difference R; is taken as shear force by the clips 18 which have suitable crosssectional area for this purpose.

The force R is such that an efficient seal is formed between the bearing face of the arched form and the bearing face of the flange of the support beam thus no additional sealing meansare required.

As shown in FIG. 8, if the bearing face of the form panel is spaced from the bearing face of the flange of the support beam 11, for example, during erection, then the force P (not indicated) due to a worker standing on the form will be opposed by the bending moment provided by the upper arm of the clip. In this instance, the bearing arm of the clip would pivot about the upper edge of the upper flange of the support beam and cause a reaction R (not indicated) which is trans-.

mitted through the internal web or stop member 22 provided for this purpose.

Again, considering FIG. 8, and an upward force D due to wind load, the panel is retained by the lower leg of the U-clip bearing on the underside of the beam. A downward force P, as discussed above, due to a worker standing on the form panel, causes the upper leg to pivot about the outer flange and bear against the stop.

It will be appreciated that the form-work for a concrete floor is built up by inserting a plurality of form panels in end-to-end abutting relationship between the beams 11.1Once the floor has been poured and has set sufficiently to allow removal of the form-work, the clip members 18 are removed by striking the downturned tag 25 with a hammer in a direction tending to remove the clip 18 from the slots 17. Once these clips 18 have been removed the form panel 10 is then free to gravitationally disengage the bottomsurface of the concrete floor.

Preferably the form panels 10 are constructed of a resilient material such as fibreglass or a suitable steel or the like and their upper surface is provided with a sur-.

face finish which does not adhere to concrete. The forms are usable many times over. Also the clip members 18 could be coated with a non-concrete adhering material, such as a parting or release agent, to ensure easy removal of the clips from the poured concrete slab. Furthermore, portion 26 could be tapered to allow easier removal.

The embodiments illustrated in FIGS. 5 and 6 are similar to that described above. However here the form panel is not provided with surrounding side walls, the outermost edges 27 of the form which engage the side members 1 l are apertured or slotted to accept the clip members 18. In addition, the beams 1 11 shown in FIG. 6 are of different construction. Flanges 121 extend from inner web 231 and are provided with upturned (and correspondingly downtumed) portions 201. There is no internal web or stop member, but provision is made for bolts 291 in the lowermost flanges 121 so that plate 181 can be bolted to the flange 121, projecting slightly beyond said flanges to provide steps 301. A form panel 102 is shown resting on one of the steps 301. No clip member is used since downward moveembodiment is less stable to wind up-draughts.

Referring now to FIG. 7, form panels 311 abut against opposite vertical sides of beam 321. Clips 331 penetrate through holes 341 in form panels 311 and into beam 321. The clips and holes are so shaped and arranged that the clips can be extracted easily when concrete 361 has set to a slab. A support 351 is shown between beam 321 and floor slab 371.

It will be realized that the apparatus according to the invention could be adapted and used in situations other than forming concrete floors. The basic requirement is that there should be a load applied to the form panels used so that they deform towards support beams. For example, the apparatus could be applied to tunnel lining with concrete or certain retaining walls.

Therefore, while the above has been given by way of illustrative example it will of course be realized that many modifications of constructional detail and design may be made to the described preferred embodiment by persons skilled in the art without departing from the broad scope and ambit of the invention as is herein set forth.

I claim: I

1. Apparatus for forming a removable false floor upon which wet concrete may be placed to from a slab, said apparatus including at least:

a. a pair of support beams which are adapted to be erected at an elevated position, at which they extend horizontally and parallel to one another, and to co-operate with removable panel support means; and,

b. a plurality of arched form panels arranged to fit neatly between said beams and to be affixed thereto by means of said Support means; said panels being removable from their operative attitude between said beams by extracting said panel support means after a concrete slab formed thereon has set, each of said support beams comprising a vertically disposed web adapted to co-operate with said panels by bearing against their edges when they are loaded and at least one horizontally disposed flange at the lower end of the vertically disposed web adapted to co-operate with said support means by preventing downward movement of said support means when said panels are loaded, said horizontally disposed flange having a vertically disposed flange at its edge remote from the vertically disposed web.

2. Apparatus according to claim 1, wherein said horizontally disposed flange is adapted to be connected to a plate comprising said support means.

3. Apparatus according to claim 1, wherein each of said form panels is of substantially rectangular form and is arched upwardly from the two parallel edges of said panel which engage with said beams and is made of resiliently deformable material, whereby when said panel is loaded with wet concrete the vertical load of the concrete tends to deflect the form panel downwardly thus urging said engaging edges firmly against said beams providing an effective seal between said form panel and said beams and an effective load transfer means from said panel to said beam.

4. Apparatus according to claim 3, characterized in that the edges of said panel are stiffened by means of a downwardly extending peripheral web arranged to prevent non-uniform deflection of said edges.

5. Apparatus according to claim 1, wherein said panel support means comprises a U-shaped clip having upper and lower legs said beam further comprising a horizontally disposed internal web adapted to bear downwardly against the upper leg of said U-shaped clip, said horizontally disposed flange being adapted to bear downwardly against the lower leg of said U-shaped Clip.

6. Apparatus for forming a removable false floor upon which wet concrete may be placed to form a slab, said apparatus including at least:

a. a pair of support beams which are adapted to be erected at an elevated position, at which they extend horizontally and parallel to one another, and to co-operate with removable panel support means; and,

b. a plurality of arched form panels arranged to fit neatly between said beams and to be affixed thereto by means of said support means; said panels being removable from their operative attitude between said beams by extracting said panel support means after a concrete slab formed thereon has set, each of said form panels being of substantially rectangular form and arched upwardly from the two parallel edges of said panel which engage said beams and made of resiliently deformable material, whereby when said panel is loaded with wet concrete the vertical load of the concrete tends to deflect the form panel downwardly thus urging said engaging edges firmly against said beams providing an effective seal between said form panel and said beams and an effective load transfer means from said panel to said beam, said form panel having an aperture in the vicinity of said engaging edges, said panel support means comprising a removable clip insertable in said aperture and into engagement with said beam to affix said form panel to said 

1. Apparatus for forming a removable false floor upon which wet concrete may be placed to from a slab, said apparatus including at least: a. a pair of support beams which are adapted to be erected at an elevated position, at which they extend horizontAlly and parallel to one another, and to co-operate with removable panel support means; and, b. a plurality of arched form panels arranged to fit neatly between said beams and to be affixed thereto by means of said support means; said panels being removable from their operative attitude between said beams by extracting said panel support means after a concrete slab formed thereon has set, each of said support beams comprising a vertically disposed web adapted to co-operate with said panels by bearing against their edges when they are loaded and at least one horizontally disposed flange at the lower end of the vertically disposed web adapted to co-operate with said support means by preventing downward movement of said support means when said panels are loaded, said horizontally disposed flange having a vertically disposed flange at its edge remote from the vertically disposed web.
 2. Apparatus according to claim 1, wherein said horizontally disposed flange is adapted to be connected to a plate comprising said support means.
 3. Apparatus according to claim 1, wherein each of said form panels is of substantially rectangular form and is arched upwardly from the two parallel edges of said panel which engage with said beams and is made of resiliently deformable material, whereby when said panel is loaded with wet concrete the vertical load of the concrete tends to deflect the form panel downwardly thus urging said engaging edges firmly against said beams providing an effective seal between said form panel and said beams and an effective load transfer means from said panel to said beam.
 4. Apparatus according to claim 3, characterized in that the edges of said panel are stiffened by means of a downwardly extending peripheral web arranged to prevent non-uniform deflection of said edges.
 5. Apparatus according to claim 1, wherein said panel support means comprises a U-shaped clip having upper and lower legs said beam further comprising a horizontally disposed internal web adapted to bear downwardly against the upper leg of said U-shaped clip, said horizontally disposed flange being adapted to bear downwardly against the lower leg of said U-shaped clip.
 6. Apparatus for forming a removable false floor upon which wet concrete may be placed to form a slab, said apparatus including at least: a. a pair of support beams which are adapted to be erected at an elevated position, at which they extend horizontally and parallel to one another, and to co-operate with removable panel support means; and, b. a plurality of arched form panels arranged to fit neatly between said beams and to be affixed thereto by means of said support means; said panels being removable from their operative attitude between said beams by extracting said panel support means after a concrete slab formed thereon has set, each of said form panels being of substantially rectangular form and arched upwardly from the two parallel edges of said panel which engage said beams and made of resiliently deformable material, whereby when said panel is loaded with wet concrete the vertical load of the concrete tends to deflect the form panel downwardly thus urging said engaging edges firmly against said beams providing an effective seal between said form panel and said beams and an effective load transfer means from said panel to said beam, said form panel having an aperture in the vicinity of said engaging edges, said panel support means comprising a removable clip insertable in said aperture and into engagement with said beam to affix said form panel to said beam. 